Spinning solution



Patented Dec. 14, 1937 v amiss SPINNING SOLUTION William Whitehead, Cumberland, Md, assignor to Celanese Corporation of America, a corporation of Delaware No Drawing. Application October 24, 1933, Serial No. 695,049

5 Claims.

This invention relates to artificial filaments, yarns or films of organic derivatives of cellulose and the method of producing them and is more especially related to the type of artificial filaments, yarns or films containing substances besides the organic derivatives of cellulose that impart to the yarns gloss or deluster and weighting efiects and to the method of producing the yarns wherein the extent of each effect may be controlled.

An object of the invention is the production of an improved yarn of a dull, opaque appearance, which yarn is uniform throughout its length as to appearance and strength.

Another object of the invention is the production of a heavily weighted yarn having normal strength, the luster of which yarn may be controlled upon its formation. Other objects of the invention will appear from the following specification.

Adding precipitants such as xylene, gasoline or kerosene to spinning solutions for spinning fine filaments of organic derivatives of cellulose by the dry method requires for the best commercial results a change in the stock type of spinning cabinets to properly maintain a uniform atmosphere surrounding the drying zone of the filaments, otherwise filaments are produced that are not uniformly precipitated along their length. Adding lubricants and weighting materials such as mineral oil, petroleum, jelly, olive oil, castor oil and other similar substances to spinning solutions for spinning filaments of organic derivatives of cellulose presents a difliculty in commercial manufacture in that upon standing, for example, from the start of spinning a batch to the completion of the spinning of that batch, there is a separation of such materials from the solution, which separation causes instability or interruption of the spinning. Lubricants have a tendency to separate from the spinning solution on standing or on heating, thus making for unstable spinning.

By the process of this invention the desirable properties of either or both of the above methods are imparted to the yarns along with other beneficial properties without experiencing the difficulties met with in either or both of the above methods. The yarn may be spun by the dry method without the necessity of special regulation of the gaseous medium into which it is spun and the spinning solution does not break down to' an unstabilized condition and, further, the yarn produced is uniform throughout its length with respect to appearance and physical properties and retains a high degree of strength. Accordingly, by this invention yarns continuously and uniformly precipitated along their length may be produced without recourse to any special spinning equipment, and yarns containing lubricants may be spun with normal or improved stability and without the separation of the lubricants from the spinning solution and yet retain the improved deluster and knitting qualities imparted to synthetic dry spun yarns by the dispersion of precipitants and lubricants in the filaments.

By the method of this invention there may be produced, by regulation of percentages of precipitants and lubricants, a yarn that is of uniform 1 dead white dullness and that shows resistance to relustering on damp ironing or treatment with swelling agents.

The yarns produced according to this invention are lubricated and pliable so that they lend themselves exceptionally well to knitting. The stitch shape of such yarns are much better than untreated yarns. The fabrics knitted from such yarns are free from pin holes and have a soft,

improved hand.

The oily material is removed from the yarn only to a very small extent in future processing and washings, thus the oily material imparts to the yarns and fabric formed therefrom a heavy soft hand.

The volatile precipitant is almost entirely removed from the yarn at the spinning cabinet and the remaining fraction is further decreased in subsequent processing of the yarn or fabric. Nevertheless, the yarns that have contained the precipitant deluster at lower temperature, shorter time and with lower soap concentration than normal yarn.

According to my invention I add to a spinning solution, of organic derivatives of cellulose, an oil or oily substance as a lubricant and weighting material, with or without quantities of a volatile non-solvent for the organic derivatives of cellulose, as a precipitant, and a saponifiable oil and/or soap and like saponifying reagents. The added materials may be in the spinning solution in a proportion as high as 40% based on the weight of the cellulose derivative. In the preparation therefore of a spinning solution about 15 to 30, say 25, parts by weight of an organic derivative of cellulose may be dissolved in about to 70, say '75, parts by weight of a solvent and to this solution is added from 1 to 8 parts by weight of mixtures of weighting materials and lubricants, saponifying agents and precipitating agents of the classes hereafter named.

The spinning solution according to this invention may be extruded through suitable orifices to form fine filaments by the dry or wet spinning methods, said filaments having a denier of, say, 1 to 10 such as used for making yarns, or they may be much heavier having a denier of, say, 50 to 2000 as used for artificial bristles, straw, etc. The invention may also be advantageously employed for making tough and pliable foils or films for photographic purposes or other purpose or for making plastics, etc.

The organic derivatives of cellulose employed as the base of the spinning solution may be organic esters and ethers of cellulose or mixtures of these. Examples of organic esters of cellulose are cellulose acetate, cellulose formate, cellulose propionate and cellulose butyrate while examples of organic ethers of cellulose are ethyl cellulose, methyl cellulose and benzyl cellulose. These esters or ethers or mixtures thereof may be dissolved in solvents such as acetone, acetone mixed with ethyl or methyl alcohol, chloroform, ethylene dichloride, ethylene dichloride mixed with ethyl or methyl alcohol and methylene chloride mixed with ethyl or methyl alcohol. The particular solvent or mixtures of solvents employed will depend uponthe kind and nature of the organic derivative of cellulose employed. The amount of the solvent used will depend upon the materials present therein and upon the type of yarn desired which information is known or easily ascertainable by the operator.

The spinning solution may contain besides the organic derivatives of cellulose eifect materials such as pigments, filling materials, dyes or lakes, fire retardants, plasticizers and sizes. Examples of fire retardants are beta chlornaphthalene, tri phenyl phosphate and tricresyl phosphate. Examples of plasticizers are the glycol and glycerol oleates, stearates, etc. and the triethanolamine oleates, stearates, etc. Examples of filling materials are powdered metals and oxides of metals. Examples of sizes are wax, gelatine with or with out hygroscopic and lubricating materials, starches, gums, salts of resin acids and glycerides.

The oil or oily material which functions in the spun yarn as a lubricant and a weighting material may be mineral oil (viscosity 65 to 110 Saybolt at 100 F), petroleum jelly, olive oil, caster oil or mixtures of these. Similar oil or oily materials may be mixed with the above or used alone. This oil or oily material or mixtures thereof are prepared so that they are dispersible or emulsifiable readily in the solvent of the spinning solution employed to dissolve the organic derivative of cellulose. The preparation of the oil or oily materials may be performed by adding to the oil or oily material small amounts of sodium, potassium or triethanolamine soap or soaps and/or a small amount of a neutral solvent such as tetrahydro-naphthalene. The preparation of the oil or oily material need not necessarily take place outside the spinning solution, the ingredients may be added to the solution separately and mixed while in the solution. In place of or in connection with the tetrahydronaphthalene there may be used sulphonated bodies such as, for example, benzene-stearo-sulphonic acid, sulphonated olive or castor oils, sulphonated mineral oils, and sulphonated bodies obtained by sulphonating mineral oils or fractions thereof, such as the sulphonated naphthenes.

As precipitating agents there may be employed such substances as xylene, gasoline, toluene, benzene, kerosene or mixtures of these. Other nonsolvents for the organic derivative of cellulose having similar boiling points to the above and that do not precipitate the cellulose derivative from solution, except when the non-solvent is present in concentrated quantity, may be employed as precipitants alone or in mixture with the above. The amount of precipitant added to the spinning solution, below certain limits, will depend upon the finish desired upon the yarn.

Vfhen oil or oily materials only or when oil or oily materials with only a small amount of a volatile precipitant are added to the spinning solution of the derivative of cellulose and its solvent, the resulting yarn spun therefrom is bright and more-or-less transparent. When oil or oily materials and suitable quantities of a volatile precipitant are added to the spinning solution of the organic derivative of cellulose and its solvent, the resulting yarn spun therefrom has a broken or porous structure and is opaque and a dull white. It has been found that the ratio of oil and oily material to volatile precipitant influences the degree of deluster, dullness, knitting qualities, etc. Thus 10% of an oily material and 5% of a precipitant, based upon the weight of the dry derivative of cellulose in a spinning solution results in a yarn that is brighter and more transparent than yarn spun from a spinning solution containing 2% of an oily material and 5% of a precipitant, based upon the weight of the derivative of cellulose. As small a. quantity as 2% of the oily material, based upon the weight of the derivative of cellulose, is found to give very noticeable improvements in the knitting quality of the yarn while as little as 2% of oily material and 2% of precipitant have been found to give substantially uniform precipitation along the length of yarn and to greatly improve the effect of heavily precipitating the yarn along its length. Higher amounts, within certain limits, of these materials in the spinning solution give a more pronounced opacity and dullness and also a more uniform precipitating effect on the cellulose derivative. Higher amounts such as 20% of oily material and 20% of precipitant in the spinning solution will give a weighted dull opaque yarn of substantially normal strength.

It is found advisable but not necessary, when the oil employed is mineral oil, to add about 10% based on the weight of the mineral oil, of a saponifiable oil to the mineral oil. An example of a saponifiable oil is olive oil.

For the purpose of further describing the invention, however, and not with the intention of limiting its scope thereto, the following examples are given.

Example I Percent Mineral oil (100 viscosity at 100 F. Saybolt) 85 Saponifiable oil (olive oil) 10 Tetrahydro-naphthalene 2.5

Soap (sodium oleate) 2.5

This spinning solution mixes, heats and filters normally with no separation. The yarn spun from this solution is bright and fairly transparent and has superior knitting properties to those of ordinary yarn as to general running qualities and stitch shape.

Example II Yarn spun from this solution has substantially the same physical properties as the yarn spun according to Example I except that the yarn is more soft and more fully lubricated.

E sample III A solution of cellulose acetate in acetone and Water is prepared according to Example I. To this solution is added based on the weight of dry cellulose acetate in the solution, of the following:

Percent Precipitant (kerosene) 50 Mineral oil (viscosity 75 at 100 F. Saybo1t) 46 Tetrahydro-naphthalene 2 Soap (sodium oleate) 2 Yarns spun from this solution are opaque, precipitated, dull and uniformly so, and has also the enhanced knitting qualities of the yarns produced according to Examples I and II.

Filaments, yarns or films formed by this invention are tough and pliable. Thus yarns may be formed of fine filaments, which yarns have to 40 more twists per inch than is commercially possible with normal yarns. Yarns or bristles made according to this invention may be formed into stronger knots, while artificial straws or ribbons or the like made according to this invention have improved plaiting qualities and may be subjected to considerably more severe processing.

It is to be understood that the foregoing detailed description is merely given by way of illustration and many alterations may be made therein without departing from the spirit of my invention.

The term oil as employed hereinafter in the claims is to be understood, unless the context requires otherwise, as covering both true oils and oleaginous materials such as petroleum jelly.

Having described my invention what I desire to secure by Letters Patent is:

1. A spinning solution for the manufacture of filaments or films by extrusion processes containing 0.5 to 5.0 parts of oil, 25 parts of cellulose acetate, 0.06 to 0.10 part of a soap, and '75 parts of an organic solvent and 0.5 to 5.0 parts of a volatile non-solvent for the cellulose acetate, the cellulose acetate and the soap being in solution in the solvent.

2. A spinning solution for the manufacture of filaments or films by extrusion processes containing 0.5 to 5.0 parts of oil, 25 parts of cellulose acetate, 0.06 to 0.10 part of a soap, 0.06 part of a sulphonated body, '75 parts of an organic solvent, 0.5 to 5.0 parts of a volatile non-solvent for the cellulose acetate, the cellulose acetate, the soap and the sulphonated body being in solution in the solvent.

3. A spinning solution for the manufacture of filaments or films by extrusion processes containing 0.5 to 5.0 parts of a non-saponifiable oil, 25 parts of an organic derivative of cellulose, 0.25 part of a saponifiable oil, 0.06 to 0.10 part of a soap, 75 parts of an organic solvent, and 0.5 to 5.0 parts of a volatile non-solvent for the organic derivative of cellulose, the cellulose derivative, the saponifiable oil and the soap being in solution in the solvent.

4. A spinning solution for the manufacture of filaments or films by extrusion processes containing 0.5 to 5.0 parts of a non-saponifiable oil, 25 parts of an organic derivative of cellulose, 0.25 part of a saponifiable oil, 0.06 part of a sulphonated body, 75 parts of an organic solvent, and 0.5 to 5.0 parts of a volatile non-solvent for the organic derivative of cellulose, the cellulose derivative, the saponifiable oil and the sulphonated body being in solution in the solvent.

5. A spinning solution for the manufacture of filaments or films by extrusion processes containing 0.5 to 5.0 parts of a non-saponifiable oil, 25 parts of cellulose acetate, 0.25 part of a saponifiable oil, 0.06 to 0.10 part of a soap and 75 parts of an organic solvent and 0.5 to 5.0 parts of a volatile non-solvent for the cellulose acetate, the cellulose acetate, the saponifiable oil and the soap being in solution in the solvent.

WILLIAM WHITEHEAD. 

